Lift boom for a front loader tractor

ABSTRACT

The lift boom is of a generally T-shaped configuration, the stem of the T-boom being provided with a hook to which any suitable load may be attached. The head of the T-boom is seated within a front loader tractor&#39;&#39;s bucket in the floor/rear wall corner. An upper cable is attached at one end adjacent the hook end of the boom&#39;&#39;s stem, and is passed over the bucket&#39;&#39;s top edge and attached at the other end to the bucket. A lower cable is attached at one end to the boom&#39;&#39;s stem intermediate the ends thereof, and is passed beneath the bucket&#39;&#39;s floor and also attached at the other end to the bucket. The lower cable is provided with a turnbuckle assembly. The turnbuckle assembly is adjustable when the boom is seated in the bucket to provide a suitable tension on both the upper and the lower cables, thereby maintaining the T-boom in the initial assembled relation with the bucket no matter what the spatial orientation of the bucket (and, hence, the boom) as set by the tractor, and no matter what the load being carried by the boom.

United States Patent 1 Leihgeber Q 1 um BOOM FOR A FRONT LOADER TRACTOR'[75] Inventor: Joseph Q. Leihgeber, Fayetteville,

[52] US. Cl. 212/35 R, 212/46 R [5]] Int. Cl. B66c 23/54 [58] Field ofSearch 212/35 R, 4, 8 R, 7

[56] References Cited UNITED STATES PATENTS 1/1958 Heimbigner 212/86/1963 Swanson 212/35 Primary ExaminerEvon C. Blunk AssistantExaminer-Hadd S. Lane Attorney, Agent, or Firm-Wood, Herron & Evans 11 3,812,979 May 28, 1974 [57] ABSTRACT The lift boom is of a generallyT-shaped configuration, the stem of the T-boom being provided with ahook to which any suitable load may be attached. The head of the T-boomis seated within a front loader tractors bucket in the floor/rear wallcorner. An upper cable is attached at one end adjacent the hook end ofthe booms stem, and is passed over the buckets top edge and attached atthe other end to the bucket. A lower cable is attached at one end to thebooms stem intermediate the ends thereof, and is passed beneath thebuckets floor and also attached at the other end to the bucket. Thelower cable is provided with a turnbuckle assembly. The turnbuckleassembly is adjustable when the boom is seated in the bucket to providea suitable tension on both the upper and the lower cables, therebymaintaining the T-boom in the initial assembled relation with the bucketno matter what the spatial orientation of the bucket (and, hence, theboom) as set by the tractor,.and no matter what the load being carriedby the boom.

8 Claims, 4 Drawing Figures LIFT BOOM FOR A FRONT LOADER TRACTOR Thisinvention relates to hoists or cranes. More particularly, this inventionrelates to a novel hoist frame particularly adapted for usewith a frontloader tractor.

Vertically swinging hoists are very well known, of course, to the priorart. Further, traveling cranes are also quite well known to the priorart. However, most prior art structures which are capable of performingthese functions are relatively complicated in nature and quiteexpensive.

A small building contractor, for example, would not be able to afford avertically swinging hoist or traveling crane. Nonetheless, a smallbuilding contractor must move heavy equipment or supplies from onelocation to another on a number of occasions during a construction job.Typical, for example, is the instance of air conditioning equipmentwhich must be moved from ground level to roof level during constructionof a twostory office building or small factory or the like. Therefore,even though a small building contractor does have occasions on which theuse of a vertically swinging hoist and/or traveling crane would beuseful, still these occasions are not substantial enough to justifyheavy captial investment in equipment designed solely for that use. I

However, most building contractors generally have available for theiruse, or own directly, a front loader tractor. A front loader tractor issimply a basic fourwheel tractor with a hydraulically operated bucketdisposed forwardly thereof, the bucket providing a payload capacitywhich quickly and efficiently allows a contractor to pick up andtransfer a payload, e.g., dirt, from one location to another. Thetractors bucket is pivotally mounted to the forward end ofa pair ofarms, those arms being pivotally connected at the rearward end to thetractors main frame. The arms are pivotally moved about their connectionwith the tractors main frame by first hydraulic means, thereby allowingthe bucket to be raised and lowered relative to ground level. Further, alinkage system connects the arms with the bucket, the linkage systembeing independently powered by second hydraulic means. The linkagesystem/second hydraulic means allows the bucket to be pivoted on itspivotal connection with the arms, thereby disposing the bucket in thatspatial orientation, i.e., upright or inverted, desired by the user.That is, the bucket can be disposed in an upright position for load ingat ground level by properly orienting the armsand bucket through use ofthe first and second hydraulic means, the bucket and payload moved aboveground level by the first hydraulic means for carrying the payload to adumping location, and then the bucket pivoted or inverted on its pivotalconnection with the arms by the second hydraulic means to dump thepayload. This type of a bucket or front loader tractor is well known tothe prior art, and is commonly available at construction sites ofresidential dwellings, small office buildings or factories, and thelike.

It has been a particular objective of this invention to provide aT-shaped lift boom which may be selectively combined with the bucket ofa bucket loader type tractor whendesired by the user so as to provide,in effect, a traveling crane having a vertically swinging hoist frame.

It has been a further objective of this invention to provide a lift boomfor a bucket of a bucket'loader type tractor that is of relativelysimple structure, relatively inexpensive to manufacture, and relativelyeasy to use, i.e., easy to mount on and dismount from the bucket.

It has been another objective of this invention to provide a lift boomwhich is adapted to be engaged with the bucket of a bucket loader typetractor regardless of the width of that bucket.

In accord with these objectives, this invention provides a lift boom ofa generally T-shaped configuration, the stern of the T-boom beingprovided with a hook to which any suitable load may be attached. Thehead of the T-boom is seated within a front loader tractors bucket inthe floor/rear wall corner. An upper cable is attached at one endadjacent the hook end of the booms stem, and is passed over the bucketstop edge and attached at the other end to the bucket. A lower cable isattached at one end to the booms stem intermediate the ends thereof, andis passed beneath the buckets floor and also attached at the other endto the bucket. The lower cable is provided with a turnbuckle assembly.The turnbuckle assembly is adjustable when the boom is seated in thebucket to provide a suitable tension on both the upper and the lowercables, thereby maintaining the T-boom in the initial assembled relationwith the bucket no matter what the spatial orientation of the bucket(and, hence, the boom) as set by the tractor, and no matter what theload being carried by the boom.

Other objectives and advantages of this invention will be'more apparentfrom the following detailed description of the invention taken inconjunction with the drawings in which:

FIG. I is a side view illustrating the T-shaped lift boom of thisinvention in operative combination with a front loader tractor;

FIG. 2 is a side view illustrating the lift boom of this invention ingreater detail, the front loader tractors bucket being shown in partialcross section;

FIG. 3 is a top view illustrating a portion of the lift boom shown inFIGS. 1 and 2 in even greater detail, the tractors bucket again beingshown in partial cross section; and

FIG. 4 is a top view similar to FIG. 3 butillustrating an alternativeembodiment of the invention.

The T-shaped lift boom 10 of this invention is shown in combination witha bucket 11 on a front loader tractor 12 in the Figures, seeparticularly FIG. 1. Note particularly that the bucket 11 includes abase or bottom floor 20, a curved rear wall 21, and planar side walls22, all such walls cooperating to define a cup-shaped bucketconfiguration. The bucket 11 may be selectively raised and loweredrelative to ground level 13 for picking up and transporting a payload,and the bucket may be selectively pivoted about pivot axis 14 fordumping the payload, by a structural assembly described in detail below.

The structural assembly by which the bucket 11 is operatively connectedto the tractor I2 is shown particularly in FIGS. 1 and 3. A liftassembly 15 provides a pair of lifting arms 16 connected adjacent thebucket by a crossbar 17, one arm being disposed on each side of thetractor 12. One end of each arm 16 is pivotally connected, as at 19, toan associated Y-shaped reinforcing frame 28 tixed in place on thetractors chassis (each side of the chassis is provided with areinforcing frame 28). The other end of each arm 16 is pivotallyconnected, as by pin 18, to ear 18a fixed to the buckets rear wall 21adjacent a side wall 22, thereby defining pivot axis 14.

A hydraulic motor 23 is provided for each arm 16. The hydraulic motor 23has its rod 24 pivotally connected, as at 25, intermediate the ends ofthe arm 16, and has its housing 26 pivotally connected, as at 27, to theassociated reinforcing frame'28. The arms 16 and hydraulic motors 23,therefore, comprise the lift assembly by which the bucket 11 may beraised and lowered relative to ground level 13. That is, uponenergization of the hydraulic motors 23 by the tractors driver, the arms16 are raised or lowered relative to ground level, thereby raising andlowering the bucket 11 relative to ground level.

A pivot assembly 30 controls the pivot motion, i.e., the upright orinverted attitude, of the bucket 11 about pivot axis 14. The pivotassembly 30 includes a bracket 31 having a collar 32 pivotally carried(on axis 33) between the ends thereof, the brackets arms 34 beingpivotally connected, as at 35, to crossbar 17. A link 36 is pivotallyconnected by pin 37 to the outer end of the bracket 31 at one end, andis pivotally connected by pin 38 between ears 39 fixed to the bucketsrear wall 21 at the other end.

The collar 32 holds a hydraulic motors housing 40 in fixed relation, themotors housing thereby being pivotally connected relative to the bracket31. The hydraulic motors piston rod 41 is pivotally connected by pin 42between ears 43 also fixed to the buckets rear wall 21, that pivotalinterconnection being on the buckets pivot axis 14 as defined by pins 18which connect the bucket 11 to the lift arms 16. Note that the pivotassembly is effectively located in a vertical plane midway between thebuckets side walls 22. Thus, the bucket 11 is pivotable about thehorizontal axis 14 by virtue of the pivot assembly 30 which includes thehydraulic motor 44, bracket 31 and link 36. That is, and since themotors rod 41 is fixed at one end to the bucket 11, as the motorshousing is forced outwardly along arrow 45 (see FIG. 1) bracket 31 iscaused to pivot counterclockwise, thereby causing the buckets mouth toface upwards or upright so as drawn by the link 36. The buckets mouth iscaused to face downwards or inverted (in a dumping attitude) by forcingthe motors housing in a direction opposite to that of arrow 45.

The lift boom 10 is of a generally T-shaped configuration, see FIG. 3.The bottom or free end 51 of the T- booms stem 52 is provided with ahook 53; note that I the hook 53 is nonadjustable relative to the stem52,

i.e., that the hook is retained on the stem in a permanent or fixedlocation. The hook 53 is hung through an eye 54 formed on plate 55 fixedto the stem 52. It is, of course, by means of the hook 53 that suitableloads may be connected to the boom 10 and, thereby, lifted and carriedby the boom as explained in detail below.

The top or head 56 of the T-boom is adapted to be seated in the rearwall/floor corner 57 of the bucket 11 itself. Notethat the booms head 56is transverse to the stem 52, and is basically tubular in configuration.The head 56 is reinforced in its orientation relative to the booms stem52 by struts 62 on both sides. An extension 58 is telescoped into eachend of the tubular head 56, that extension being extendable from eachend of the head into face contact with the inside surface of the bucketsside walls 22. The extensions 58 are retained in predetermined, extendedpositions by suitable lock devices such as a key 59 that passes throughconcentric holes 60 aligned in the extension 58 and head 56. It is thistelescoping structure of the head 56 that allows the stem 52 of the boom10 to be located in substantially planar relation with the center plane61 of the tractors bucket 11. Further, telescoping extensions 58 allowthe boom 10 to be cooperatively engaged with a bucket 11 ofsubstantially any width. 1

In operative position with the bucket 11, the head 56 of the T-boom 10is seated against the rear corner 57 of the bucket where thefloor 20meets the curved rear wall 21, the booms stem 52 touching neither thetop edge 63 nor the bottom edge 64 of the bucket; this attitude is shownin FIG. 2. The T-boom 10 is maintained in this attitude by cable meanswhich are adjustably connected in tension to the buckets ribs or ears39, 43 on the rear face of the rear wall 21.

An upper cable 65 is fixed at one end to eye 66 of member 55 mounted onthe free end 51 of the T- booms stem. The upper cable 65 is passed overthe top edge 63 of the bucket 11, and is looped (as at 67) around a pin68 mounted on one of the buckets ears 39 at the other end. Tubularshield 69 is located on the upper cable 65 where the cable passes overthe buckets upper edge 63, thereby eliminating chafing and possiblebreakage of the cable due to rubbing on the buckets upper edge.

A lower cable 70 is attached at one end to an eye 71 defined by member72 fixed to the boom 10 intermediate the ends of the booms stem 52. Thelower cable 70 passes under the bottom edge 64 and floor 20 of thebucket 11, and is fastened by a loop 73 onto a pin 74 mounted on one ofthe buckets ears 43 at its other end. Tubular shields 75, 76 for thelower cable 70 are located at potential places of binding such as thebuckets bottom edge 64 and the corner 57 edge for the same reasons notedabove in connection with shield 69.

A turnbuckle assembly 77 is interposed in the lower I cable 70 betweenthat end where it is fixed to the T- booms stem 52, and that end whereit is connected to the bucket 11. This turnbuckle assembly 77 isprovided for the purpose of adjusting the tension on the upper 65 andlower 70 cables, tightening of the turnbuckle assembly in the usualmanner causing an increase in the cable tension, i.e., a tightening ofthe cables. The tension on the calbes 65, 70, as provided by theturnbuckle assembly 77, maintains the T-boom 10 in the desired attitudeshown in FIG. 2 no matter what the spatial orientation of the bucket 11(and, hence, of the boom 10). That is, no matter how close to verticalthe boom 10 is oriented, the boom is prevented from pivoting on an axisdefined by head 56 by means of the cable 65, 70 attachment system.

In use, the T-shaped boom 10 is fixedly connected to and, in effect,made an integral part of the tractors bucket 11 by virtue of the cables65, 70 and the turnbuckle assembly 77. Thus, as the bucket 11 is movedvertically relative to ground level 13, and as the bucket is tilted ormoved about pivot axis 14, by the relevant hydraulic motors 23, 44, asdesired by the operator, the booms hook 53 (and, hence, the loadthereon) may be located relative to ground level and relative to thetractor itself as desired by the operator. Therefore, the

boom l/bucket ll/lift l and pivot 30 assemblies is in the nature of ahoist frame which can be moved from side to side by repositioning thetractor, and which can be swung vertically by means of the hydraulicmotors 23, 44. Further, the overall combination is in the nature of atraveling crane in that any load carried thereon may be moved fromlocation to location as desired by the operator.

The T-boom structure and configuration of the alternative embodiment isbasically the same as illustrated in connection with the embodimentshown in FIGS. 1-3. The main difference lies in the cable means by whichthe T-boom 10 is retained in desired spatial orientation within thebucket ll itself. The tractors bucket 11 structure, arm I6 structure,and hydraulic motor 23, 44 structure is the same as for that embodimentillustrated in FIGS. l-3.

As mentioned, the difference between the alternative embodiment and theFIGS. l-3 embodiment lies in the structure of the cable means. In thealternative embodi: ment, a double top cable 81a, 81b and a doublebottom cable 82a, 82b is provided each pair of these cables defining aV-like configuration relative to the stem 52 of the T-boom 10. Each ofthe top cables 81a, 81b is connected to eye 66 fixed to the top of theboom s stem 52. Each cable 81a, 81b extends from the eye 66 to a pointwhere it is connected to pin 83a, 83b, respectively, fixed at 84a, 84bto side ribs 18a closely adjacent the side walls 22 of the bucket 11. Asillustrated in FIG. 4, the stem 52 of the T-boom 10 is broken as at 85,and the top cables 81 are broken at 86, so that the location of each topcables joinder to the stem, as well as'the joinder of each top cable tothe bucket 11, may be shown. Each top cable 81a, 81b is provided with atubular shield 87 adapted to overlie the top edge 63 of the bucket 11 toprevent chaffing of the cable as it passes over the bucket.

As noted, the alternative embodiment shown in FIG. 4 also includesdouble bottom cables 82a, 82b, each of the bottom cables being connectedat one end to eye 71 fixed to the underside of the boom's stem 52 and atthe other end to a pin, (not shown) fixed to the buckets ribs 18aadjacent the side walls 22in a manner similar to that illustrated inFIG. 2 for the single cable 70 embodiment. Each of the lower cables 82a,82b is provided with a turnbuckle assembly 88a, 88b thereby allowingtension on the upper cables 81a, 81b to the suitably adjusted so thatthe T-shaped boom is maintained in a desired spatial orientation withinthe bucket 11. Further, shields 89 are provided on each of the lowercables to prevent chaffing of the cable on the lower edge 64 of thebucket as they pass thereunder.

Having described in detail the preferred embodiment of my invention,what I desire to claim and protect by Letters Patent is:

l. The apparatus combination comprising:

a lift boom and a front loader tractor, said tractor including anopen-mouth bucket having a rear wall and opposite side walls, saidbucket being movable up and down relative to ground level by a liftassembly and pivotable about a pivot axis between upright and invertedpositions by a pivot assembly,

said lift boom including a head arid a stem of generally T-shapedconfiguration,

the head of said lift boom being seated inside'said bucket against saidrear wall thereof, and the stem of said lift boom extending outwardlyfrom said bucket,

hook means connected to said stem for connecting a payload to said boom,and

cable means interconnecting the bucket and the stem of said lift boom ata point forward of the mouth of said bucket, said cable means serving tomaintain said lift boom in immobile operational assembly with saidbucket in a vertical plane, thereby permitting said hook means to beoriented relative to said ground level as desired by an operator throughthe use of said lift and pivot assemblies.

2. The apparatus of claim 1 wherein said cable means includes a memberextending from said boom outwardly of said bucket to said bucket andhaving a turnbuckle assembly allowing the tension on said cable means tobe suitably adjusted for maintaining said boom in immobile operationalassembly with said bucket. I

3. The apparatus of claim 2wherein said cable means includes an uppercable and a lower cable, each attached to the lift booms stem outwardlyof said bucket at one end, and said lower cable being adapted to passunder the bottom edge of said bucket and connect therewith at its otherend, said turnbuckle assembly being connected with one of said cables.

4. The apparatus of claim 3 including shields interposed on said cableat points of potential chaffing of said cable on said buckets structure.

5. The apparatus of claim 3 wherein said cable means includes at least apair of upper cables each attached to the lift booms stem at one end,the other end of each of said cables being connected with said bucketadjacent said opposite side walls.

6. The apparatus of claim 1 wherein said head is tubular, and includingan extension in telescoped assembly with at least one end of saidtubular head, said extension being extendable from said head so as toallow said head, to extend between said side walls, thereby providinglateral stability to said boom when said boom is seated in said bucket.

7. The apparatus of claim 6 including an extension telescoped into eachend of said head,

thereby allowing said stem to be located at a desired plane between saidbuckets side walls.

8. The apparatus of claim 7 wherein said plane is midway between saidside walls.

1. The apparatus combination comprising: a lift boom and a front loadertractor, said tractor including an open-mouth bucket having a rear walland opposite side walls, said bucket being movable up and down relativeto ground level by a lift assembly and pivotable about a pivot axisbetween upright and inverted positions by a pivot assembly, said liftboom including a head and a stem of generally T-shaped configuration,the head of said lift boom being seated inside said bucket against saidrear wall thereof, and the stem of said lift boom extending outwardlyfrom said bucket, hook means connected to said stem for connecting apayload to said boom, and cable means interconnecting the bucket and thestem of said lift boom at a point forward of the mouth of said bucket,said cable means serving to maintain said lift boom in immobileoperational assembly with said bucket in a vertical plane, therebypermitting said hook means to be oriented relative to said ground levelas desired by an operator through the use of said lift and pivotassemblies.
 2. The apparatus of claim 1 wherein said cable meansincludes a member extending from said boom outwardly of said bucket tosaid bucket and having a turnbuckle assembly allowing the tension onsaid cable means to be suitably adjusted for maintaining said boom inimmobile operational assembly with said bucket.
 3. The apparatus ofclaim 2 wherein said cable means includes an upper cable and a lowercable, each attached to the lift boom''s stem outwardly of said bucketat one end, and said lower cable being adapted to pass under the bottomedge of said bucket and connect therewith at its other end, saidturnbuckle assembLy being connected with one of said cables.
 4. Theapparatus of claim 3 including shields interposed on said cable atpoints of potential chaffing of said cable on said bucket''s structure.5. The apparatus of claim 3 wherein said cable means includes at least apair of upper cables each attached to the lift boom''s stem at one end,the other end of each of said cables being connected with said bucketadjacent said opposite side walls.
 6. The apparatus of claim 1 whereinsaid head is tubular, and including an extension in telescoped assemblywith at least one end of said tubular head, said extension beingextendable from said head so as to allow said head to extend betweensaid side walls, thereby providing lateral stability to said boom whensaid boom is seated in said bucket.
 7. The apparatus of claim 6including an extension telescoped into each end of said head, therebyallowing said stem to be located at a desired plane between saidbucket''s side walls.
 8. The apparatus of claim 7 wherein said plane ismidway between said side walls.